Overheating 5.2l 94' grand cherokee

[ryansmaid]

I have a 94' Grand Cherokee that overheats when I'm idleing or sitting in traffic. I replaced the headgaskets (because they were blown), had the heads rebuilt, new radiator, thermostat, installed a heavy duty fan clutch with new high flow fan blades. In other words everything I can think of. I have rechecked the heads and there is no exhaust gas in the system. It has no electric fan because there is no room for one (trust me I have measured it twice:x).

I'm thinking it may be a circulation problem and installing a high flow water pump. Any ideas before I do that?

P.S. Today I ran vinegar in the system for a good hour to try and clean the block and it didn't seem to make a difference.

 

[baggman]

I have a 94' Grand Cherokee that overheats when I'm idleing or sitting in traffic. I replaced the headgaskets (because they were blown), had the heads rebuilt, new radiator, thermostat, installed a heavy duty fan clutch with new high flow fan blades. In other words everything I can think of. I have rechecked the heads and there is no exhaust gas in the system. It has no electric fan because there is no room for one (trust me I have measured it twice:x).

I'm thinking it may be a circulation problem and installing a high flow water pump. Any ideas before I do that?

P.S. Today I ran vinegar in the system for a good hour to try and clean the block and it didn't seem to make a difference.

Seems like you've done all I would have suggested. Since it only overheats when in idle, I would think that it would be a flow/circulation problem. What kind of belts do you have on a '94 5.2? My '98 5.2 only has the serpentine belt. If the fan is belt driven it may be loose enough to where you only get good circulation while driving. I'm really grasping here, like I said before, it seems you've done everything else.....

 

[FloridaCherokee1988]

I would have to agree about a circulation problem, could be a clog or something but usually the vinegar method solves that problem.

 

[SteelHeadz]

Radiator cap checked ok?